cp's OEIS Frontend

A072822 The terms of A073215 (sums of two powers of 23) divided by 2.

%I A072822 #15 Apr 09 2025 19:47:20
%S A072822 1,12,23,265,276,529,6084,6095,6348,12167,139921,139932,140185,146004,
%T A072822 279841,3218172,3218183,3218436,3224255,3358092,6436343,74017945,
%U A072822 74017956,74018209,74024028,74157865,77236116,148035889,1702412724
%N A072822 The terms of A073215 (sums of two powers of 23) divided by 2.
%F A072822 T(n,m) = (23^n + 23^m) / 2, n = 0, 1, 2, 3 ..., m = 0, 1, 2, 3, ... n.
%e A072822 T(2,0) = 265 = (23^2 + 23^0) / 2.
%e A072822 Triangle begins:
%e A072822         1;
%e A072822        12,      23;
%e A072822       265,     276,     529;
%e A072822      6084,    6095,    6348,   12167;
%e A072822    139921,  139932,  140185,  146004,  279841;
%e A072822   3218172, 3218183, 3218436, 3224255, 3358092, 6436343;
%e A072822   ...
%t A072822 Union[#/2&/@(Total/@Tuples[23^Range[0,7],{2}])]  (* _Harvey P. Dale_, Apr 21 2011 *)
%o A072822 (Python)
%o A072822 from math import isqrt
%o A072822 def A072822(n): return 23**(a:=(k:=isqrt(m:=n<<1))+(m>k*(k+1))-1)+23**(n-1-(a*(a+1)>>1))>>1 # _Chai Wah Wu_, Apr 09 2025
%Y A072822 Cf. A073215.
%K A072822 nonn,tabl,easy
%O A072822 0,2
%A A072822 _Jeremy Gardiner_, Jul 21 2002
%E A072822 Offset changed by _Alois P. Heinz_, Apr 09 2025